The United States Department of Energy's Pittsburgh Energy Technology Center, under its Combustion 2000 program, is working with private industry to develop two kinds of advanced, coal-fired electric power generation systems that will have significantly higher thermal efficiency, superior environmental performance and a lower cost of electricity than current coal-fired plants. The low emission boiler system (LEES) is a highly advanced pulverized-coal-fire power plant which will be ready for commercial introduction before the year 2001. LEES uses supercritical steam conditions and substantial low-level heat recovery to achieve an efficiency of 42%. Very low emissions are realized by using advanced combustion technology and pollution controls that are integrated with the boiler. The high performance power system (HIPPS) is based on indirectly fired combined-cycle technology that is capable of 47-50% efficiency. This system uses a gas turbine driven by a clean air working fluid separately heated in a novel high-temperature furnace. Energy recovered from the turbine exhaust drives a steam cycle. HIPPS is planned to be commercially available by 2005. This paper describes the Combustion 2000 program and the technologies being developed for LEES and HIPPS.